title: Liquid-liquid transition in a strong bulk metallic glass-forming liquid.
abstract: Polymorphic phase transitions are common in crystalline solids. Recent studies suggest that phase transitions may also exist between two liquid forms with different entropy and structure. Such a liquid-liquid transition has been investigated in various substances including water, Al2O3-Y2O3 and network glass formers. However, the nature of liquid-liquid transition is debated due to experimental difficulties in avoiding crystallization and/or measuring at high temperatures/pressures. Here we report the thermodynamic and structural evidence of a temperature-induced weak first-order liquid-liquid transition in a bulk metallic glass-forming system Zr(41.2)Ti(13.8)Cu(12.5)Ni10Be(22.5) characterized by non- (or weak) directional bonds. Our experimental results suggest that the local structural changes during the transition induce the drastic viscosity changes without a detectable density anomaly. These changes are correlated with a heat capacity maximum in the liquid. Our findings support the hypothesis that the 'strong' kinetics (low fragility) of a liquid may arise from an underlying lambda transition above its glass transition.
authors.affiliation: Materials Science and Engineering Department, Saarland University, Campus C63, 66123 Saarbrücken, Germany. shuai.wei@mx.uni-saarland.de
authors.forename: Shuai
authors.identifier: 0000000330512480
authors.initials: S
authors.lastname: Wei
authors.forename: Fan
authors.initials: F
authors.lastname: Yang
authors.forename: Jozef
authors.initials: J
authors.lastname: Bednarcik
authors.forename: Ivan
authors.initials: I
authors.lastname: Kaban
authors.forename: Olga
authors.initials: O
authors.lastname: Shuleshova
authors.forename: Andreas
authors.initials: A
authors.lastname: Meyer
authors.forename: Ralf
authors.initials: R
authors.lastname: Busch